OMAHA, Nebraska — Lawyers for a former doctor accused of killing four people with ties to an Omaha medical school argued in a hearing Friday that evidence gathered during his arrest should be excluded from his trial.

Anthony Garcia's attorneys — Robert Motta Jr. and Alison Motta of Chicago — said in a Douglas County District Court hearing that police did not have probable cause to arrest Garcia in southern Illinois in July 2013. They also argued that search warrants used to track Garcia's movements in the weeks before his arrest and to seize his cellphone, laptop, GPS and other devices were unconstitutionally overbroad.

"They went on a fishing expedition, and the law clearly says you can't do that," Alison Motta said.

Garcia, 41, of Terre Haute, Indiana, is charged with four counts of first-degree murder and various weapons counts. He is accused of fatally stabbing Thomas Hunter, the 11-year-old son of Creighton pathologist William Hunter, and the family's housekeeper, Shirlee Sherman, in 2008.

Garcia also is charged in the May 2013 deaths of Creighton pathologist Roger Brumback and his wife, Mary.

Authorities say Garcia was motivated by revenge for being fired from Creighton's pathology department in 2001. He has pleaded not guilty. Authorities have testified that searches of Garcia's devices turned up GPS searches for the Brumbacks' home on May 12, 2013 — the day they were believed to have been killed — as well as for the home of another Creighton pathology doctor whose home was broken into, but who was not at home and not harmed.

Officials say they also determined through records searches that Garcia had used a credit card at an Omaha restaurant on the same day.

When Garcia was arrested, he was being watched by a task force of officers. They arrested him after they said he turned south on Interstate 57 in Illinois because authorities worried he was headed to Louisiana State University, from which he was fired in 2008.

An FBI agent testified in November that authorities feared Garcia would go to Louisiana and harm members of the LSU medical staff.

Garcia was initially arrested on suspicion of following too closely and driving under the influence. A Nebraska warrant charging him with the Omaha slayings was issued roughly five hours later.

Other warrants that allowed the task force to track Garcia's whereabouts using his cellphone and other devices should be void because, the Mottas argue, Nebraska warrants should be limited to tracking devices located within the state's boarders — not devices that were in Indiana and Illinois.

"Because the government illegally tracked Anthony Garcia into both public and private places ... the arrest has to be found unlawful, and all items found in his vehicle and on his person have to be thrown out," Alison Motta said. "Everything that stems from that initial illegality would have to be thrown out."

Prosecutor Don Kleine defended the legality of the search warrants and the evidence seized from them, pointing to case law that has found that those who carry a cellphone equipped with a GPS "have no expectation of privacy."

Douglas County District Judge Duane Dougherty gave both sides several weeks to respond with their objections and support of the search warrants.